Cover for suction boxes of paper-making machines



Sept. 8, 1931. A. J. MORIN 1,822,363

COVER FOR SUCTION BOXES OF PAPER MAKING MACHINES Filed Nov. 24, 1930 .Art z/r ffiar/w.

Patented Sept. 8, 1931 UNITED STATES PATENT OFFICE ARTHUR J. MORIN, OF AUBURN, MASSACHUSETTS, ASSIGNOR TO RICE, BARTON & FALES, INC., WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS COVER FOR SUCTION BOXES OF PAPER-MAKING MACHINES Application filed November 24, 1930. Serial No. 49?,728.

This invention relates to an improved cover for a suction box employed in a paper making machine.

The suction box used in a. paper maklug machine consists of a box extending the width of the machine and having a perforated cover over which the wire apron or felt carrying the pulp or paper is drawn.

A pumping device is attached to the box to create a partial vacuum therein so that moisture and water will be drawn down from the pulp or paper as the wire apron or felt is drawn over the suction box.

The covers for these suction boxes have usually been made of long wooden perforated strips or of a series of perforated wooden blocks.

It has been a difiicult matter to get these suction boxes to operate perfectly for if there is leakage between the wire apron or felt and the perforated cover, the suction is apt to be broken or unduly lowered. This difiiculty is particularly encountered in connection with the long wire apron or screen is employed in a Fourdrinier paper making machine. As these aprons are usually made of bronze or brass Wire. wear will take place on both the wire and the covers of the suction boxes leading to the difiiculty before referred :3 to. This necessitates frequent replacement of the covers. It therefore is a common practice to keep a supply of these covers in a wet place so that when used they will be wet or penetrated with moisture whereby they will be in the condition in which they are em ployed on the machine. This is an expensive practice and one that is not altogether successful, because obviously it is diflicult to mantain the wooden covers under exactly the moisture conditions encountered in use.

I found that most of the above difficulties can be overcome by impregnating the wood with a lubricant or preservative which may be tallow, oil or paraflin. I have obtained the best results by using tallow.

The Wood may be impregnated by putting the same in molten tallow and, if desired, by applying pressure to force the tallow into the pores of the wood. The wood may be dried if desired before the in'ipregnation with the lubricant or preservative takes place.

I have found by treating the wood this way that the same will not shrink or swell materially when put into use under moisture conditions. I have also found that wood treated in this manner will last longer owing to the lubricating effect of the tallow.

I also havc found that it takes much less power to draw a wire apron or felt over suction boxes constructed according to my improvement and that the wire apron or felt will last much longer. I also have found that the wire apron is less apt to seize or tear covers constructed according to my improvement.

Oneapplication of the intention is illustrated in the accompanying drawings, in which Fig. 1 is a plan view of a suction box cover constructed according to my invention;

Fig. 2 is an end elevation of the same;

Fig. 3 is a cross sectional elevation on an enlarged scale: and

Fig. -1 is a perspective view of one of the sides of the cover.

The cover consists of two side pieces A--A which may be secured to the top of the suction box. Each of these. side pieces is provided with a tennon B. The cover C is made up of a series of perforated wooden blocks each of which is preferably made in the shape of a lozenge. The blocks are provided with dove-tailed slots D to fit on the tennons of the side pieces.

The perforations in the block C are set preferably to come out of line with the travel of the apron or felt.

As the common practice. in aper-making machines is to produce very wide paper, it will be seen by the arraingements before described that the cover can be made of any desired length.

The blocks C are preferably made out of maple wood impregnated with tallow which causes the same to shrink in size and take up considerable weight. This impregnation can be done by putting the blocks in molten tallow. Then if desired a heavy pressure can be applied to the molten tallow.

As before stated, other methods can be employed for impregnating the blocks with a lubricant, but the one described is the one now best known to me for practicing the invention.

A suction box cover constructed as above V described keeps its shape a long time, wears very slowly and very evenly and reduces wear on the wire or felt.

The details and arrangements herein shown and described may be greatly varied by a skilled mechanic without departing from the scope of my invention as expressed in the claims.

Having thus fully described my invention, what I claim and desire to secure by Letters Patent is:

1. A suction box cover for a paper-making machine consisting of wood impregnated with a lubricant.

2. A suction box cover for a paper-making machine consisting of wood impregnated with a preservative.

3. A suction box cover for a paper-making machine consisting of wood impregnated with tallow.

4. A suction box cover for a paper-making machine consisting of a series of perforated wooden blocks impregnated with a lubricant.

5. A suction box cover for a paper-making machine consisting of a series of perforated wooden blocks impregnated with tallow.

G. A suction box cover for a paper making machine consisting of a series of perforated wooden blocks impregnated into a preservative.

In testimony whereof I have hereunto afiixed my signature.

ARTHUR J. MORIN. 

